1. Field of the Invention
The present invention relates generally to a protocol structure for a CDMA (Code Division Multiple Access) communication system, and in particular, to an apparatus and method for ensuring multimedia service and high rate data transmission in a mobile communication system.
2. Description of the Related Art
In general, a mobile communication system should provide a high throughput when transmitting data at high data rate. In the radio protocol of the mobile communication system, the function blocks of an RLP (Radio Link Protocol) layer, a MUX (Multiplex) layer, and a physical layer are very significant in determining performance. Interfacing and information flow between layers are also important in order to achieve a high throughput during a high rate data transmission.
Existing mobile communication systems, particularly IS-2000, HDR (High Data Rate) proposed with the technology of the 1XEV of the 3GPP2, and the 1XTREME do not ensure a high throughput when providing a high rate data service because they are not configured suitably for multimedia service, let alone for optimization of throughput in a packet data service.
With regard to HDR, a physical channel transmits only data with the same QoS (Quality of Service) level. Although it transmits/receives multiple data, the HDR system supports only non-real time service. A physical layer, scheduling, and signaling are designed in the HDR system to support high rate non-real time data service to users within a cell. Another problem with the HDR system is that QoS control cannot be carried out according to different priority levels of multiple input data and different priority levels within an input data. When an Internet data service, a voice service, and a multimedia service are provided contemporaneously to a user, the services have different priority levels. The voice service must be provided in real time, and the multimedia service, and the Internet data service may be provided in real time or non-real time. Due to the QoS control limitation, the HDR system cannot ensure different QoS levels to intra-media data and inter-media data. The other conventional systems exhibit the same shortcomings. That is, the conventional mobile communication systems cannot offer different QoS levels to intra-media data or inter-media data and as a result, cannot provide multimedia service.